A photoplethysmogram (PPG) signal may be obtained from a pulse oximeter, which employs a light emitter and a light sensor to measure the perfusion of blood to the skin of a user. The PPG signal may be compromised by noise due to motion (e.g., acceleration) artifacts. That is, movement of the body of a user may cause the skin and vasculature to expand and contract, introducing acceleration artifacts into the PPG signal. While such acceleration artifacts may be at least partially compensated for, there remains a problem of determining accurate heart rate measurements even after such partial compensation. When presented with various heart rate values over sampling times within a time interval, it is often difficult to determine the most probable heart rate for each sampling time and consequently the most probable heart rate path considering the multiple possible candidate paths from one sampling time to the next over the overall time interval.